Valve-gear for steam and other fluid-pressure engines.



No. 803,342. PATENTED OCT. 31, 1905. G. HOWARD & G. GIBBS. VALVE GEARFOR STEAM AND OTHER FLUID PRESSURE ENGINES.

APPLIUATION FILED MAYQ. 1904.

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G. HOWARD & G. GIBBSi PATENTED OCT. 31, 1905.

VALVE GEAR FOR STEAM AND OTHER FLUID PRESSURE ENGINES.

APPLICATION FILED MAY 9. 1904.

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No. 803,342. PATENTED OCT. 31-, 1905.' G. HOWARD & G. GIBBS. VALVE GEARFOR STEAM AND OTHER FLUID PRESSURE ENGINES.

APPLICATION FILED MAY9. 1904.

3 SHEETS-SHEET 3.

Ann. I. Glnuu 00,. Mrs-mm. maximum. 0. c

UNITED STATES PATENT OFFICE.

GEOFFREY HOWARD AND GEORGE GIBBS, OF BEDFORD, ENGLAND VALVE-GEAR FORSTEAM AND OTHER FLUID-PRESSURE ENGINES.

Specification of Letters Patent.

Patented Oct. 31, 1905.

Application filed May 9, 1904. Serial No. 207,172.

To all whom it may concern:

Be it known that we, GEOFFREY HOWARD and GEORGE GIBBs, engineers,subjects of the King of Great Britain, residing at Britannia IronWVorks, Bedford, in the county of Bedford, England, have inventedcertain new and useful Improvements Relating to Valve-Gear for Steam andother Fluid-Pressure Engines, of which the following is a specification.

This invention has reference to valve-gear for steam and otherfluid-pressure engines, and is particularly applicable to the control ofthe steam-distributing valve of a mechanical stoker of the kind in whichthere is a reciprocating ram or pusher for introducing the fuel into thefurnace, the said ram operating by steam or other fluid under pressureadmitted to and exhausted from the Working cylinder by thedistributing-valve, which is automatically actuated at periodicalintervals that can be prolonged or diminished, as required, by adjustingthe valve-gear.

It is the chief object of our present invention to so construct thevalve-gear that it will not be appreciably affected by the changes inthe position of the mechanical stokeror other fluidpressure engine thatarises from the rolling and pitching of aship, the said valve-gear beingthus rendered applicable equally well to mechanical stokers or otherfluid-pressure engines, whether they be used for marine or landpurposes.

Another object of our invention is to utilim with the said. valve-geartwo adjustable dash-pots or similar contrivances, which by reason oftheir adjustability render it possible to vary the duration of thepauses at the end of each stroke of the piston. We are thus able tocontrol the number of fuelcharges fed to the furnace in a given time andalso to obtain the necessary amount of time for the fuel to descend fromthe hopper in front of the ram-piston for completelyfilling the space infront of the ram before an ensuing feed-stroke recurs. The said gearalso enables the ram to remain in its forward position after performingthe feed-stroke and to thus avoid the fire from the furnace from findingits way back into the feed-hopper, as is necessary in mechanical stokersof the kind referred to.

In order that our said invention may be clearly understood and readilycarried into effect, we will describe the same with references to theaccompanying drawings, in Which- Figure 1 isaside elevation of thevalve-gear applied to a mechanical stoker of the kind hereinbeforementioned. The parts are in this figure represented in the position theyoccupy when the distributing-valve is admitting motive fluid to thefront end of the cylinder to cause the piston and ram to perform abackward stroke. Fig. 2 is a plan, and Fig. 3 an end elevation, of thesaid valve-gear. Fig. 4: is a side elevation similar to Fig. 1, but withthe parts in the position they assume when the said distributing-valveoccupies the position for cutting off the motive fluid and the pistonand ram have completed their rearward stroke. Fig. 5 is a similar View,but with the parts in the position they assume when thedistributing-valve occupies the position for admitting the motive fluidto the back end of the cylinder for causing the piston and ram toperform their forward stroke. Fig. 6 is a cross-section takenapproximately on the line 1 1 of Fig. 1. Figs.

7, 8, 9, and 10 are elevations showing separately some of the parts usedfor actuating and controlling the distributing-valve. Fig. 11 is alongitudinal sectional elevation taken approximately on the line 2 2 ofFig. 6.

In all the figures like letters of reference indicate similar parts.

A is the steam or other fluid-pressure cylinder.

B is the piston.

O is the distributing-valve.

D is the ram or pusher, which is connected with the piston by the rod B.D is the chamber in which said ram or. pusher works. The fuel issupplied to said chamber through an opening D from a hopper situatedabove the opening, said fuel being thrust forward into the furnace bythe advance of the pusher, as is well understood in this class ofapparatus. The said distributing-valve is in the example illustrated ofthe reciprocating piston type actuated bya finger carried by a spindlec, that extends through a hearing or sleeve 0, forming part of thesteam-chest A. The spindle c'of the distributing-valve O is IOOsurrounded by a sleeve or boss 0, which extends through the steam-chestA and carries a pair of loose and independent arms of and a looseoscillatory lever g. The arms 0 and f are connected at or near theirouter ends with dash-pots e and f, respectively, and the lever g isconnected, by means ofa rod g with the ram or pusher D. Fixed to theouter end of the valve-spindle 0 is a cross-piece 0 which is capable ofbeing actuated by any one of the said three arms or levers f g, forwhich purpose the said cross-piece has aflange 0 projecting in the pathof the arm a and a flange 0 projecting in the path of the arm f. Thesaid lever g also has projections g which are adapted to actuate thesaid arms a and f. It also has a projection that actuates thecross-piece 0 When fluid under pressure is admitted, say, to the frontend of the cylinder A by the valve C, which then occupies the positionrepresented in Fig. 1, the piston B moves backward and retracts the ramD, at the same time angularly shifting the lever g in a backwarddirection. As this lever r continues its backward movement itsprojection g engages with the arm f, and thus raises the latter. At thesame time the projection g of said lever g leaves the arm 0 and permitsit to descend by the action of gravity at a speed which is controlled bythe dash-pot 0'. By the time the piston reaches the rearward end of itsstroke the projection of the lever g has turned the cross-piece c andtherefore the valve 0, into the position to cut off the supply of themotive fluid to the cylinder. (See Fig. 4:.) The piston and its ram thenremain in this position at the rearward end of their stroke, while thearm 0 descends by the action of gravity and under the control of itsdashpot a. As the said arm completes its descent it strikes the flange cof the cross-piece and turns the latter into a position to cause thevalve 0 to admit the motive fluid to the back end of the cylinder. (SeeFig. The piston and ram then perform their forward stroke and at thesame time move the lever g angularly into its forward position, Fig. 1,which operation causes said lever to again raise the arm a by means ofits projection g and to turn the cross-piece 0 into a position to bringthe valve G into its shut-off position. During this movement the arm fis liberated by the projection 9, so that it descends by the action ofgravity at a certain speed, which is under the control of its dashpot f.In completing its descent the said arm f actuates the cross-piece 0through the flange c", and thereby sets the valve 0 into the positionfor again admitting the motive fluid to the front of the cylinder andagain retracting the piston and ram. A fresh cycle of operations similarto that already described is then performed, whereby the apparatuscontinues working and automatically supplies the fuel to the furnace.The said dash-pots and f have valves 0 f for regulating the speed atwhich the arms a and f can descend, so that the duration of time thatelapses at each pause between the strokes of the piston and ram can beregulated at will for the purposes hereinbefore stated. The dash-pot eis somewhat analogous to a door-check and works with atmospheric air.The dashpot 7 works with liquid, such as oil.

Although our invention is especiallyintended for use with mechanicalstokers having a fluid-pressure Working cylinder, it may obviously beapplied to fluid-pressure engines used for other purposes thanmechanical stoking.

What we claim, and desire to secure by Letters Patent of the UnitedStates, is

1. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the valve, and an oscillatory lever adapted to alternatelyelevate and retain said arms in an elevated position and alternatelyactuate the cross-piece in opposite directions in advance of itsactuation by said arms. thereby closing the valve and temporarilyshutting off the supply of motive fluid until the crosspiece is actuatedby one of said arms.

2. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the valve, an oscillatory lever adapted to alternately elevateand retain said arms in an elevated position and alternately actuate thecross-piece in opposite directions in advance of its actuation by saidarms, thereby closing the valve and temporarily shutting off the supplyof motive fluid until the crosspiece is actuated by one of said arms,and means for retarding the downward movement of said arms.

3. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the Valve, an oscillatory lever adapted to alternately elevateand retain said arms in an elevated position and alternately actuate thecross-piece in opposite directions in advance of its actuation by saidarms, thereby closing the valve and temporarily shutting ofi the supplyof motive fluid until the crosspiece is actuated by one of said arms,and a dash-pot connected to each of the said arms for retarding thedownward movement thereof.

4:. In valve-gear and other fluid-pressure engines, means fortemporarily arresting the movement of the piston at each end of itsstroke, said means comprising the combination with thedistributing-valve,of a crosspiece connected therewith for opening andclosing it, a pair of gravity-movable arms adapted to alternately engagesaid cross-piece for opening the valve, and an oscillatory lever havingits upper end provided with a pair of outwardly-extending projectionsand an intermediate projection, said outwardly-extending projectionsadapted to alternately elevate and retain said arms in an elevatedposition and said intermediate projection adapted to alternately actuatethe cross-piece in opposite directions in advance of its actuation bysaid arms, thereby closing the valve and temporarily shutting off thesupply of motive fluid until the cross-piece is actuated by the downwardmovement of one of said arms.

5. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the valve, an oscillatory lever having its upper end providedwith a pair of outwardly-extending projections and an in termediateprojection, said outwardly-extending projections adapted to alternatelyelevate and retain said arms in an elevated position and saidintermediate projection adapted to alternately actuate the cross-piecein opposite directions in advance of its actuation by said arms, therebyclosing the valve and temporarily shutting off the supply of motivefluid until the cross-piece is actuated by the downward movement of oneof said arms, and means for retarding the downward inovementof saidarms.

6. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the valve, an oscillatory lever having its upper end providedwith a pair of outwardly-extending projections and an intermediateprojection, said outwardly-extending projections adapted to alternatelyelevate and retain said arms in an elevated position and saidintermediate projection adapted to alternately actuate the cross-piecein opposite directions in advance of its actuation by said arms, therebyclosing the valve and temporarily shutting off the supply of motivefluid until the cross-piece is actuated by the downward movement of oneof said arms, and a dash-pot connected with each of said arms.

7. 1n valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the valve, an oscillatory lever adapted to alternately elevateand retain said arms in an elevated position and alternately actuate thecross-piece in opposite directions in advance of its actuation by saidarms, thereby closing the valve and temporarily shutting off the supplyof motive fluid until the crosspiece is actuated by one of said arms,adashpot connected to each of the said arms for retarding the downwardmovement thereof, and means for regulating the degree of the retardationof each of the dash-pots.

8. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it, a pair ofgravity-movable arms adapted to alternately engage said cross-piece foropening the valve, an oscillatory lever having its upper end providedwith a pair of outwardly-extending projections and an intermediateprojection, said outwardly-extending projections adapted to alternatelyelevate and retain said arms in an elevated position and saidintermediate projection adapted to alternately actuate the cross-piecein opposite directions in advance of its actuation by said arms, therebyclosing the valve and temporarily shutting off the supply of motivefluid until the cross-piece is actuated by the downward movement of oneof said arms, a dashpot connected with each of said arms, and means forregulating the degree of the rotation of each of the dash-pots.

9. In valve-gear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of acrosspiece connected therewith for opening and closing it and providedwith a pair of flanges, a pair of gravity-movable arms adapted toalternately engage the flanges of the cross-piece for actuating thelatter, thereby opening the valve, and an oscillatory lever having itsupper end provided with a pair of outwardlyeXtending projections and anintermediate projection, said outwardly-extending projections adapted toalternately elevate and retain said arms in an elevated position andsaid intermediate projection adapted to actuate the cross-piece inopposite directions in advance of its actuation by said arms, therebyclosing the valve and temporarily shutting off the supply of motivefluid until the cross-piece is actuated by the downward movement of oneof said arms.

10. In valve-gear and other fluid-pressure engines, means fortemporarily arresting the movement of the piston at each end of itsstroke, said means comprisingthe combination with thedistributing-valve, of a crosspiece connected therewith for opening andclosing it and provided with a pair of flanges, a pair ofgravity-movable arms adapted to alternately engage'the flanges of thecross-piece for actuating the latter, thereby opening the valve, anoscillatory lever having its upper end provided with a pair ofoutwardly-extending projections andan intermediate projection, saidoutwardlyextending projections adapted to alternately elevate and retainsaid arms in an elevated position and said intermediate projectionadapted to actuate the cross-piece in opposite directions in advance ofits actuation by said arms, thereby closing the valve and temporarilyshutting off the supply of motive fluid until the cross-piece isactuated by the downward movement of one of said arms, and means forretarding the downward movement of the said arms.

11. In valvegear and other fluid-pressure engines, means for temporarilyarresting the movement of the piston at each end of its stroke, saidmeans comprising the combination with the distributing-valve, of-acrosspiece connected therewith for openingand closing it and providedwith a pair of flanges, a pair of gravity-movablearms adapted toalternately engage the flanges of the crosspiece' for actuating thelatter, therebyopening the valve, an oscillatorylever having its upperend provided with a pair of outwardlyextending projections and anintermediate projection, said outwardly-extending projec tions adaptedto alternately elevateand retain said arms in an elevated positionand-said intermediate projection adapted to actuate the cross-pieceinopposite directions in advance of its actuation by said arms, therebyclosing the valve and temporarily shutting off the supply of motivefluiduntil the cross-piece is actuated by the downward movement of one ofsaid arms, and a dash-pot connected with said arms for retarding thedownward movement thereof.

12. In valve-gear and other fluid-pressure engines, means fortemporarily arresting the movement ofthe piston at each end of itsstroke, said means comprising the combination with thedistributing-valve, of a crosspiece connected therewith for opening andclosing-it and provided with a pair of flanges, a-pairo'fgravity-movable arms adapted to alternately engage the flangesof thecross-piece for actuating the latter, thereby opening the valve, anoscillatory lever having its upper end provided with a pair ofoutwardly-extending projections and an-intermediate projection, saidoutwardly-extending projections adapted to alternately elevate andretain said arms in an elevated position and said intermediateprojection adapted to actuate the cross-piece in opposite directions inadvance ,of'its actuation by said arms, thereby closing the valveand-temporarily shutting off the supply of motive fluid until thecross-piece is actuated by the downward movement of one of said arms, adash-pot connected with said arms for retarding the downward movementthereof, and means for regulating the degree of the retardation of eachof the dash-pots.

' In testimony whereof we have hereunto set our hands, in presence oftwo subscribing wit nesses, this 26th day of'April, 1904.

GEOFFREY HOWARD. GEORGE GIBBS.

Witnesses:

CHARLES J AMES MARSHALL, ERNEST GEORGE BRANDON.

